Figure 34 Self-Balancing Control Station
Self-balancing describes a control station in which the non-operating mode output signal follows
(tracks) the operating mode output signal. When the control station is in the automatic mode,
the manual output signal will follow the automatic output signal. Once the controller is
transferred to the manual mode, the output signal will remain at its previous value until one of
the manual push buttons (discussed below) is depressed. Then, the output will vary. When the
controller is in manual mode, the automatic output signal will track the manual output signal.
Once the controller is transferred from the manual to automatic mode, the automatic output signal
will initially remain at the manual mode value. If a deviation did exist in the manual mode, the
automatic output signal would change slowly and return the controlled variable to setpoint.
The deviation indicator, setpoint indicator, setpoint adjustment thumbwheel, and output meter of
the controller in Figure 34 function essentially the same as those in Figure 32. The remaining
controls and indicators are quite different. Therefore, each will be discussed.